Boring mill



Jan. 15, 1963 B. Hoi-'FMANN BORING MILL 4 Sheets-Sheet l Filed Dec. 2l,1959 H' JNVENToR.

BERNHARD HoFFMANw BY l i v @m QL @L ATTORNEYS Jan. 15, 1963 B. HOFFMANNy 3,073,185

BORING MILL 4 Sheets-Sheet 2 Filed Dec. 2l, 1959 JNVENToR. FQNHARDHOFFMANN FmiY AT TOE-N EVS Jan. 15, 1963 B. HOFFMANN 3,073,185

BORING MILL Filed Dec. 2l, 1959 4 sheets sheet 3 H YDRAU LIC CYUNDERSEff AxLEbgAUGme Ems l sq TRAN S- TOOL 27 BOX i`|*.fT" i "T T". H ea ii-4..1 1 L j LJ-d-u SYMCHRO CONTROL A TRANSFORMER- TOOL A @Aueme TOOLSW1-mmm@ RACK Posmmue CONTROL MOTOR SENSE CONVERTER AND D. c. 7 ELECTRICAM PMR/l HYDRAUUC REVEEEVE@ CYUNDER Mum-TURN POTENTIOMETEE Fora HNE TOOLADJUSTMENT QM @E ATTORN Eys Jan. 15, 1963 B. HOFFMANN 3,073,185

BORING MILL Filed Dec. 2l, 1959 4 Sheets-Sheet 4 INVENTOA BERNHARDHOFFMANN United States Patent vO 3,073,185 BORING MILL Bernhard Homann,Hamilton, Ohio, assigner to Baldwin- Lima-Hamilton Corporation,Hamilton, Ohio, a corporation of Pennsylvania Filed Dec. 21, 1959, Ser.No. 861,002 3 Claims. (Cl. 77-4) The present invention relates broadlyto boring mills, and, more specilically, to an improvement in a carwheel boring machine which sets the radius of the boring toolsautomatically.

In present day practice the boring of car wheels, whether they be ofcast iron or steel, has been greatly simplified due to the variousautomatic features that have been incorporated into wheel boringmachines of the hydraulic type. These machines have been designed tosuch a degree of versatility that the car wheel is automatically chuckedand then bored by roughing and finishing cutters and chamfered inthe'same series of operations. Furthermore, during said operations themachine is designed to be fed at dilerent speeds with the speed changesbeing automatic-between the rough cutting, finish cutting, chamteringand tool withdrawal operations. Thus, the operations of such a machineare substantially continuous and automatic, resulting inmaximum'production, yet requiring a minimum of time Iand effort on thepart of the operator. t

At the present time, in finishing carl wheels preparatory to mountingthem upon axles, it ,i'sfne'cessary to .measure the diameter of the axleto be fitted with a conventional'-,

micrometer-and then bore the hub opening inthe car wheel to the properdiam-eter, which is usually @slightly less than the diameter of the,axle, so that .thefwliee'l will have a drive vfit on the axle. Thepractice by the railroadsof refinishing car wheels embodiessubstantiallythe. same 'op-u erations as employed in finishing new car wheels, inthat,

the Wheel is removed from the axle and the bore of the car wheel is thenrefinished preparatory to mounting ,said wheel upon a new or arelinished axle. It is, however, necessary that a skilled machinistmeasure the diameter of the new axle with a micrometer, adjust thecutters so as to bore a hole the idiameter of which shall-beslightly'lessthan the diameter of the axle in order to ensure that thewheel will havefa proper drive fit when mountedupon said axle.

urements be taken of one part and manually transferred to another partin setting up the boring mill. lWhile the boring and chamferingoperations are automatically .performed "by the borin'g mill machine,the measurements necessary for properly positioning the cutting` toolsdependsupon a correct and accurate measurement being obtained byaimachinist, which always brings into being the possibility of an errordeveloping that could result in the entire Wheel being improperly boredand thus subject to being scrapped.

One of the objects of the present invention is to provide a car wheelboring machine that is automatic in operation for boring the hubs of acar wheel.. v l

Another object is to provide a car wheel boring machine having a boringbar with tools adjustably mounted therein Aand means for adjusting saidtools radially of the boring bar commensurate with the. diameter of anaxle upon which the car wheel is to be mounted.

Another object is to provide a car Wheel boring ma-- chine having avertically reciprocating boring bar with adjustable cutting toolscarried thereby and motor means disposed within said boring bar forradially adjusting said cutting tools dependent upon the diameter whichthe car wheel is to be mounted.

While the-foregoingtype of operation hasy proven 'to b esatisfactory'andacceptable, it .does require that measof an axle upon ice Other objectsand advantages, more or less ancillary to the foregoing, in the mannerin which all of the various objects are realized, will appear in thefollowing description which, when considered in connection with theaccompanying drawings, sets forth the preferred embodiment of theinvention.

Referring to the drawings, wherein the preferred embodiment of theinvention is illustrated:

FIG. l is a fragmentary vertical sectional view of a car Wheel boringmachine embodying the present invention incorporating a `diagrammaticrepresentation of an axle gauging mechanism associated therewith;

FIG. 2 is an enlarged fragmentary detailed sectional view of the lowerportion of the boring bar with the cutting tools disposed therein, thesection lbeing taken on tion of an axle gauging station withaxlecentering wings,v

in position to receive an axle to be'gauged; and

FIG. 7 is a fragmentary view of the parts shown 1in, FIG. 6 with thecentering wings. yclosed about an axle,t andthe gauging feeler in itssensing position.

Referring to FIG. 1, ..there is s hown va table 10 that -is rotatablymounted'upon a bedofa conventional boring machine, such as thet'ype.disclosed'in:Patent'2,6l9,854z

of December 2, 1 95'2,` to Schu-rr. rotatable 'table 1`0f has mounted,fon the Upper face thereof,- a plurality of spaced ychuck jaws 11 thatare slidably supporte d upo suitable .guide members, not shown,iwh;ichextendradi of the table 10. The chuck jaws.1'1 areadapted 'to engag, andretain a car wheel 12 in proper position to have worlg` operationsAperformed thereon by suitable boring bars. A frame 14 is adapted to besupportedby. the' bedof the boring machine and it, inturnycarr'ies acylindrical,

guidefl'Sin which is mounted a verticalboring bar '15 The frame 14 alsohas v`mounted thereon af hydraulicf motor which is. adapted to operatethe bor-ing bar 16 in avertical reciprocatory manner within; the Aguide15. T hej hydraulic motor 17 consists of a piston 18 operatingyyith,

a cylinder 19 and having a c'onnecting'rod 20 mounted,}

thereon which is turn connects the piston with. the boring` bar, 16through the. connecting member 21. A The` hydr lic motor 17 is providedwith inlet and outlet connections..

-22 at each end thereof, which are adapted tol be connected to asuitable hydraulic pump, notvshown, for the delivery of uid underpressure to cause ,reciprocation of the piston, 1 8 withi'ril thecylinder 1'9 and the resultant movement of the boring lbar 1-6. Suchmechanism is conventional in the art. i x 4 The hollow v boring bar 16has mounted in the upper; portion thereof, in any suitable manner, areversible motor 24.v The reversible driving motor 24 has a conventionalnut drive which engages a splined screw (not shown) to cause areciprocation of a shaft member 25. The direction of reciprocation ofthe shaft member depends on the direction of rotation of the motor 24.The reciprocatingshaft member 25 carries or is drivingly connected witha rack member 25a whichextends substantially theme11-,l

. tire length of the boringv bar 16 with the lower end of thefn rackmember projectingat an extreme of its movement into a suitable cap orhousing 26 provided on the bottom or lower face of the boring bar. Therack member 25a` is supported by suitable bearing members 27 providedat'y 'l spaced points within the lower end of the boring bar 1'6 toinsure its proper alignment within the boring bar and its engagementvvith'the driving means of the motor 24;

The boring bar 16 is provided with three cutting tools, with thelowermost tool 28Y being a rough boring tool, while ajnishing boringtool 29 is disposed midway between'pthe'roughboring tool '28 and achamfering tool 30. The three tools are radially adjustable within theboring bar'l. In the form of adjustment 'shown in the drawings, each ofthe tools has associated therewith a spurv pinion which isy adapted toengage the rack member a so that upon reciprocatorymovement of the rackmember, the spury pinions 32 will be rotated to either advance orretract the toolsradially vof the boring bar. The three cutting toolscarried by the boring bar 16 are mounted therein for adjustment inthesame identical manner; thus, a description `with respect to one ofthetools will readily apply'to the others.

"Asashown in FIGS. 2 and 3, the boring bar 16 is provided withadiametricallyV extending passageway or hole 33 which opens out throughthe opposite sides of the boring bar. The passageway 33 has slidablymounted therein appair of tool carriers 34 and 35 which have theirouterendsformed to receive" the desired replaceable cut.-

ting tools '36. Each tool carrier is providedv with an intdrnallythreaded 'socket 37 which extends from its inner end short of its outerend, and when the tool carriers are mounted in longitudinal alignmentfor` placement in the passageway 33,'the same are connected by a doubleended,

adjustable screw member 3.8'. One end of the screw member 38 is providedwith left-hand threads and the other end of the'v screw memberisprovide'd with' rightfhand threads, and "thescrew, rnerriberl isthreaded into theA threaded sockets 3 7 formed -irr the carriers 34 and35. d ,Y

ejc'e'ntral portion of theV screw member 38, FIG. 3, hastlieabove-mentioned spurpinion 32 mounted thereon for engagement with therack .member 25a', 'soA that upon reciprocatory movement of the rackmember 25a the spur pinionA 32frwill bev rotated in a complementarydirection which in turn'pwill rotate the screw member 38 causing thetool holders 34l and 35 to be either retracted or advanced radiallyofthe boring bar16' depending on the direction of movement of the rack25a. By providing threads of appropriate pitch on the screw member 3Sand socket 37, the cutting members are capable of being radiallyadrvancedl or'retracted v to a degree complemental to the degr'ee ofreciprocatory movement of the rack` member and the rotative movement ofthe spur pinion 32.

The boring bar 16 is'provided with a passage 40, FIG.

3, that 'is transverse of the` passageway 33 and adaptedv toiriteifs'ectsaid'passageway so that the bearing members ZTmay be mounted within theboring bar 16 and retained therein' by cap sc reit'ls 41 to insure theretention of the rack member irr'engagement with the" spur pinion 32. Asi sho` n in FIG. 2,` the tool 'holders'34 and 35 areretainedv 1n`f 'dpassageway 33 by means of adjustable wedges 43 which'v 'are held in*engagement with one another by a screw member 44, so that said wedges 43will insure the ret'etionof the tool carriers within the passageway 33o`f`tliefboring bar 16, yet vstill permit the tool carriers to have aradially adjusting movement within the cutting barv upon vthe. rotativelmovement Aof the screw member 38. 'lhel removal of the screwfm'ember 44enables the wedges 43` to..be withdrawn, thereby 'permitting the to'olcarriers 34; and 35 to; be' removed from the boring bar as a unit` sothat the tool carriers can be replaced.

The presentY invention `is particularlyV directed to. the combinationof, elementsgwhich causes an adjusting actuationv of;v the tooladjusting motorY 24 by tn eans'ofl which theradial positions of both theroughing tools 28 and the l tools v'2.9, are .setvr to the properdimension. As previo l no ted', .the1 size of the boreiinished by theseltools iside Y xleinc'zles the usual bearing area,

ed. by automatically gauging an `vaxle on which .i

d wheeiistto, be drives.4 An eine to be need with n ted generally inFIGUREY l and. in. Y 75 dust guard and wheel seat at each end. Since thepresent invention is concerned only with a machine which willautomatically bore a set of wheels to fit the wheel seat of a givenaxle, no detailed disclosure of the axle itself need be made.

The axle A is received on a measuring fixture in any suitable manner,and the sequence of operations hereinafter described starts at thispoint. Referring to FIGS. 6 and 7, the axle A is permitted to roll downan incline to a point where it overrides an actuating switch whichcontrols, in any suitable manner, the hydraulic circuit to a wingactuating cylinder 51. The piston within the cylinder 51 is moveddownwardly by the hydraulic force of the cylinder and causes a slide 52to move downwardly. The slide has pivoted thereto a pair of axleengaging wings 53 and 54 in the form of bell crank levers pivoted to astationary portion of the mechanism at 55 and 56 respectively. Thus, assoon as the axle A passes the actuating switch 50, the Wings commence tomove in and to clamp the axle in the centered position shown in FIG. 7.

As can be seen in FIG. 7, the axle engaging wing 53 carries a small pin57 which engages the axle when the wing is in its fully closed position.This pin is forced to the left by engagement with the axle and closes anactuating switch 58 which starts the tool gauging mechanism inoperation.

Closing the switch 58l actuates the hydraulic circuit of a cylinder 59connected to an axlegauging rack 60. The rack is attached directly orindirectly to the piston which is within the cylinderl 59, and the rackcarries at its nose portion a feeler member 61 which engages the wheelseat of the axle as shown in FIGS.k 1 and `6.

Meshed with the rack 60* is a pinion gear 62 which is carried by theshaft of a synchro transmitter 63 so that the armature offthetransmitter vis rotated as the rack moves in towards the axle, and theextent of its rotation willv be determined by the extent of the movementnecessary for the feeler 61 tok engagev the wheel seat of the axle.

A synchro follower 64 is electrically connected to the transmitter 63land, .of course, follows its movements so thatl the angular movement ofthe follower is precisely the same as the angular movement of thetransmitter.

As will be seen from FIG. 4, the follower 64 carries a pinion 65 whichis in meshing engagement with a follower rack 66. This assembly iscarried by the boring bar housing and projects through the side wallthereof ina suitable bearing 67. The follower rack 66 has a toolengaging feeler 68 on its inner end so located as to engage the cuttingedge of the finishing tool 29 as best shown inv FIG. 2..'I`he rack 66 ismoved inwardly by a vhydraulic cylinder 69 to the point where the feeler68A engages lthe' tool.

It should be` assumed that the resetting of the tools v starts with thetools in their innermost position each'time is energized to bring thefinishing tool 29to `the Yradially outward position in which contactwith the `feeler 68 is made after-which the motor continues to operateso long as'an imbalance exists betweenthe angular position of thesensing synchro 63 and the follower synchro y64. The

unbalancing signal is suitably amplified and y'fed to the.

motor 24 asA` an Voperating voltage in a`known manner.

The outward movement of the tool'against the feelei" 68 takes place'vagainst the pressureof the fluid in cylinderl 69, andthis movement'corrects the position of the follow'-VIA er synchro 64 by actuating"pinion 65 Vthroug'l'l rack" Y66.V

wheel of the proper diameter to receive an axle of the size that is thenengaged by the feeler of the synchro transmitter 63.

Obviously, movement of the rack 25a to adjust the iinishing tool 29 tothe proper radial position simultaneously causes a radial adjustingmovement of the roughing tool 28 and the chamfering tool 30. The toolsare then in an adjusted position and the roughing and iinish cut of awheel blank placed on the machine will exactly coincide with thedimension established by the feeler 68 which, in turn, coincides withthe dimension of the axle A established by the gauging tool feelermember 61.

The boring tools having been properly positioned radially by the actionof the motor 24 through the rack mechanism 25a described above, a carwheel 12 is placed upon the chuck jaws 11 mounted on the rotatablemachine table 10, and the vertical boring bar 16 is moved downwardly ina conventional manner to bring iirst the rough boring tool 28 intoengagement with the car wheel. After the rough boring operation, theiinishing tool 29 is brought into position and the bore finished. Asabove noted, the action of the boring bar is conventional and is causedby piston 18 moving downwardly within cylinder 19. When the nishing tool29 has passed through the bore of the wheel hub, the chamfering tools 30are subsequently brought into engagement with the edge of the car wheelhub to impart a chamfer to the hole which has been previously machinedby the rough and finished boring tools. The downward movement or strokeof the boring bar 16 and the degree or depth of cut of the chamferingtool 30 is determined by an adjustable stop rod 48 carried in the boringbar guide 15. The stop rod 48 is provided with an adjustable mechanism49 for positioning the upper end of the stop rod to engage an outwardlyprojecting abutment formed on or carried by the upper end portion of thehollow boring bar 16. Thus, with the stop rod outwardly positioned bythe adjusting mechanism 49, the abutment 49a on the hollow boring bar 16will engage the upper end of the rod 48 thus stopping the movement ofthe boring bar and of the chamfering tool 30. The stopping of thedownward movement of the boring bar causes the hydraulic motor 17 to bereversed so that the piston 18 will be moved upwardly. This reversal ofmovement at the end of the machine operation is conventional. In thecase of the present invention, the upward movement of the boring bar isaccompanied by an inward movement of the tools, so that by the time theboring bar has reversed to the point that the finishing tool would passthrough the hole that has been previously bored, the tools have beenretracted by energizing the motor 24 and the finishing and roughingtools can both pass through the bored hub so that the hub will not bescored as sometimes occurs with conventional machines.

The upward movement of the boring bar and the inward movement of thetools continue until a limit switch 70, which can take any suitableform, is actuated by some such means as a depression 71 in the boringbar body. When the limit switch drops into the depression the upwardmovement of the boring bar is stopped and the parts are ready for a newsetting. 'I'he limit switch 7i) is wired to act as an interlock, in anysuitable manner, so that no energy can pass into or out of the synchros,and no adjusting movement of the racks 60 and 66 can be made until theboring bar is in such a position that the finishing tool 29 is oppositethe feeler FIG. 5 indicates diagrammatically a system in which two wheelseats are gauged consecutively so that a pair of wheels will be producedfor the `axle A. It may be desirable, in some instances, to use a singleaxle gauging mechanism and to transport this mechanism from one wheelseat to the other. If desired, however, duplicate axle gauging devicescan be provided and con- 6;. nected to an appropriate switchingmechanism so that onev or the other will close the circuit to thefollower synchro 64 and its associated rack 66.

No attempt has been made in the present specication to show the exactelectrical circuits or hydraulic circuit involved since these are wellknown in the art. While various of the elements are showndiagrammatically, various modiications and changes will suggestthemselves to those skilled in the art, and such modifications may bema-de without departing from the scope of the appended claims. l

What I claim is:

l. In a boring mill having a rotatable table for supporting a car wheelor the like, a hollow boring bar positioned in a plane transverse tosaid table for engagement with said car wheel, motor means associatedwith said boring bar for advancing and retracting said boring bar withrespect to said car Wheel, means for providing relative rotatablemovement between said boring bar and the car wheel, a plurality of toolsslidably mounted for radial adjustment in said boring bar, means mountedin said boring lbar for reciprocatory movement therein and engageablewith said tools |for radially advancing and retracting said tools withrespect to said boring bar, means connected to said reciprocatory meansfor driving said reciprocatory means, feeler means, means for lineallymoving said feeler means into contact with an axle on which the carwheel is to be mounted, centering means for positioning the axlecentrally in the path of s aid feeler means, switch means actuated bysaid centering means when the axle is `centered to actuate said feelermoving means to move said feeler means into contact with the axle, andmeans responsive to said feeler means for energizing said drive means toadvance said tools radially to a position such that the diameter of ahole drilled thereby in the car wheel bears a predetermined relationshipto a diameter of the axle.

2. In a boring mill having a frame and a rotatable Itable iforsupporting a car wheel or the like, a guide carried by said frame, ahollow 4boring bar mounted in said guide for reciprocatory movement intoand out of engagement with said car wheel, a hydraulic motor mounted onsaid frame and engageable with said boring bar for actuating same, areciprocatory rack member mounted in said boring bar, a motor in saidboring bar, driving means carried by said motor and engageable with saidrack member, said boring bar having an opening therethrough, a pair ofradially disposed spaced cutters slidably mounted in said opening andprovided with opposed axially aligned internally rig-ht and left handthreaded bores, a spur pinion mounted in ysaid opening between saidycutters and having right and left hand threaded extensions on oppositesides thereof engaging the threads in said bores, said rack memberengaging said spur pinion for radially advancing and retracting saidcutters with respect to said boring bar upon the movement of said rackmember, means including a synchro transmitter to sense Ithe diameter ofan axle to which a wheel is to be fitted, a synchro follower actuatedmeans to gauge the radial position of one orf said tools to bore a wheelto a diameter established by said synchro transmitter, and connectingmeans between said motor and said synchro follower to advance said toolsradially of said boring bar to the position established by said synchrotransmitter.

3. In a boring mill having a rotatable table for supporting a car wheelor the like, a hollow boring bar positioned in a plane transverse tosaid table for engagement with said car wheel, means associated withsaid boring bar for advancing and retracting said boring bar withrespect to said car wheel, a plurality of tools slidably mounted forradial adjustment in said boring bar, means reciprocally mounted in saidboring bar and engageable with said tools for advancing and retractingsaid tools radially of the boring bar, a motor mounted in said boringbar, driving meansl carried by said motori and engageable with saidreciprocally-mounted means, first eeler means adjustable to adiameter ofan axle to which a kWheel is to be tted, rst responsive means responsiveto the position of said feeler means, second lfeeler means, means formoving said second feeler means into contact with one of said tools,second responsive means responsive to the position of said second feelermeans and cooperatingwith said irst responsive means to gauge the radialposition of said one tool yto bore a wheel to a diameter established bysaid rst responsive means, and connecting means between said motor andsaid second responsive means to advance said tools radially of saidboring bar to the position established by said first responsive means.

References Cited in the le of this patent UNITED STATES PATENTS HardenOct. 22, 1895 WoytychA Feb. 2, 1937 Nye June 23, 1942 Christman July 23,1946 Trornov Jan. 22, 1957 Hennessy Oct. 15, 1957 Townsend Mar. 18, 1958Wagner et al. July 22, 1958 Wor-then Dec. 30, 1958 f Howey etal July 19,1960 FOREIGN PATENTSr Great Britain Sept. 10, 1940

3. IN A BORING MILL HAVING A ROTATABLE TABLE FOR SUPPORTING A CAR WHEELOR THE LIKE, A HOLLOW BORING BAR POSITIONED IN A PLANE TRANSVERSE TOSAID TABLE FOR ENGAGEMENT WITH SAID CAR WHEEL, MEANS ASSOCIATED WITHSAID BORING BAR FOR ADVANCING AND RETRACTING SAID BORING BAR WITHRESPECT TO SAID CAR WHEEL, A PLURALITY OF TOOLS SLIDABLY MOUNTED FORRADIAL ADJUSTMENT IN SAID BORING BAR, MEANS RECIPROCALLY MOUNTED IN SAIDBORING BAR AND ENGAGEABLE WITH SAID TOOLS FOR ADVANCING AND RETRACTINGSAID TOOLS RADIALLY OF THE BORING BAR, A MOTOR MOUNTED IN SAID BORINGBAR, DRIVING MEANS CARRIED BY SAID MOTOR AND ENGAGEABLE WITH SAIDRECIPROCALLY-MOUNTED MEANS, FIRST FEELER MEANS ADJUSTABLE TO A DIAMETEROF AN AXLE TO WHICH A WHEEL IS TO BE FITTED, FIRST RESPONSIVE MEANSRESPONSIVE TO THE POSITION OF SAID FEELER MEANS, SECOND FEELER MEANS,MEANS FOR MOVING SAID SECOND FEELER MEANS INTO CONTACT WITH ONE OF SAIDTOOLS, SECOND RESPONSIVE MEANS RESPONSIVE TO THE POSITION OF SAID SECONDFEELER MEANS AND COOPERATING WITH SAID FIRST RESPONSIVE MEANS TO GAUGETHE RADIAL POSITION OF SAID ONE TOOL TO BORE A WHEEL TO A DIAMETERESTABLISHED BY SAID FIRST RESPONSIVE MEANS, AND CONNECTING MEANS BETWEENSAID MOTOR AND SAID SECOND RESPONSIVE MEANS TO ADVANCE SAID TOOLSRADIALLY OF SAID BORING BAR TO THE POSITION ESTABLISHED BY SAID FIRSTRESPONSIVE MEANS.